Soils as a Key Component of the Critical Zone 6

Philippe Lemanceau is Director of Research at INRA, France, where he directs the UMR Agroecology. He is a soil microbiologist and specializes in soil biodiversity and plant/microorganism interactions.Manuel Blouin is Professor of Ecology at AgroSup Dijon, France, and a member of the UMR Agroecology. His research focuses on the effect of soil organisms on plant growth, development and health.

• Foreword ixChapter 1. Life in the Soil: From Taxonomy to Ecological Integration 1Manuel BLOUIN, Philippe HINSINGER, Patrick LAVELLE and Philippe LEMANCEAU1.1. Importance of soil organisms 11.2. Historical perspective 31.2.1. Fauna: convergence between soil science and ecology 31.2.2. The root system of plants: the hidden side of plant ecology 51.2.3. Microorganisms: from tool development towards conceptual developments in ecology and evolution 71.3. Structure of this book 111.4. References 12Chapter 2. Diversity of Mechanisms Involved in Soil Ecological Interactions 17Manuel BLOUIN2.1. Various interactions 172.2. A diversity of ecological mechanisms 212.2.1. Trophic relationships 212.2.2. Physical modification 252.2.3. Chemical modification 252.2.4. Biochemical modification 272.3. A unique conceptual framework for trophic and non-trophic interactions 302.4. Research perspectives: the case of plant–earthworm–microorganism relationships 312.5. References 34Chapter 3. Biodiversity and Ecological Functioning of Soils 39Jean-Christophe LATA, Sébastien BAROT, Julie LELOUP,Thomas LERCH, Naoise NUNAN and Xavier RAYNAUD3.1. Importance of biodiversity in the functioning of soils 393.1.1. A diversity whose functional importance has been recognized late 393.1.2. Impact of biodiversity on soil functioning 423.2. Main current research questions 433.2.1. Biodiversity–function links impacted by abiotic parameters and disturbances 443.2.2. Biodiversity–functions and nutrient cycles 463.2.3. Development of approaches and techniques 493.2.4. Awareness of the importance of biodiversity in the functioning of soils for human societies 523.3. References 53Chapter 4. Plant–Microorganism Interactions in the Rhizosphere 57Philippe LEMANCEAU, Matthieu BARRET, Manuel BLOUIN, Sylvie MAZURIER and Barbara PIVATO4.1. The rhizosphere: a site of multiple exchanges 574.2. Recruitment of microorganisms in the rhizosphere 594.3. Plant–microorganism interactions: a long history 624.4. Rhizospheric microbiota: benefits for the plant 664.5. Plant–microorganism interactions in agroecology 694.6. Conclusion and perspectives 724.7. References 72Chapter 5. Interactions between Soil and Vegetation: Structure of Plant Communities and Soil Functioning. 83Grégoire T. FRESCHET, Cyrille VIOLLE, Catherine ROUMET and Éric GARNIER5.1. Introduction 835.1.1. The soil–plant interactions at the core of ecosystems 835.1.2. Characterizing the interactions between plants and soil: response traits, effect traits and feedback loops 845.2. Soil as a major determinant of plant community structure and ecosystem properties 855.2.1. Main determinants of the structure of plant communities 855.2.2. Which soil variables influence vegetation? 865.2.3. Role of spatial and temporal heterogeneities of the soil 895.3. Effects of vegetation on soil functioning 905.3.1. Biogeochemical cycles 905.3.2. Macrostructure and aggregation 975.3.3. Relationship with soil biodiversity 985.4. Conclusion 995.5. References 100Chapter 6. Soil Fauna: Determinants of Community Structure and Impacts on Soil Functioning 105Jérôme CORTET, Sophie JOIMEL, Johanne NAHMANI and Mickael HEDDE6.1. Soil fauna: classification and quantification 1056.1.1. Towards a systemic understanding of soil 1066.1.2. Towards a necessary intraguild description: example of soil microarthropods 1086.2. Abiotic and biotic determinants 1106.2.1. Pedoclimatic constraints 1106.2.2. Anthropogenic constraints 1116.3. Diversity–operation relations 1126.3.1. Taxonomic diversity 1126.3.2. Functional diversity based on traits: a tool in development 1146.4. Fauna: a bioindicator of soil quality 1156.5. References 118Chapter 7. Molecular Ecology of Soil Organisms: The Case of Earthworms 125Lise DUPONT7.1. Introduction 1257.2. Species identification 1277.3. Modes and systems of reproduction 1287.4. Population genetic structure 1297.4.1. Gene flow 1297.4.2. Genetic variation in populations 1327.5. Phylogeography 1337.6. Adaptative selection 1347.7. Conclusion 1347.8. References 134Chapter 8. Feedback Loops in Soils: Evidence and Theoretical Implications 139Jérôme MATHIEU8.1. Soils, complex or complicated systems? 1398.2. Importance of feedback loops in system operation 1418.2.1. Simple indirect interactions in ecosystems 1428.2.2. Feedback loops in soils 1448.3. Consequences of feedbacks on the systems 1498.3.1. Eco-evolutionary dynamics 1498.3.2. Emerging properties 1508.3.3. Hierarchical organization, ascending and descending causality 1518.3.4. Self-organization 1538.3.5. Hysteresis 1538.3.6. Stable alternative states 1548.3.7. Responses of complex systems to an external disturbance 1558.4. Conclusion 1588.5. References 158Chapter 9. Actions and Feedback: Consequences for Soil Management 163Sébastien BAROT, Manuel BLOUIN and Philippe LEMANCEAU9.1. Emergence of an eco-evolutionary understanding of the functioning of soils 1639.2. Towards ecological and evolutionary soil engineering 1669.3. References 169List of Authors 173Index 177